1. Field of the Invention
The present invention relates to a method and a system for selecting a plurality of base stations to position a mobile device, and more particularly, to a method and a system which utilize a plurality of artificial neural network units for selecting a plurality of base stations to be to a plurality of base station sets, so as to position a mobile device.
2. Description of the Prior Art
In the development of wireless communications and the mobile device, it has become an important issue to accurately estimate a current position of the mobile device and to correspondingly provide wireless communication services from a plurality of base stations. In the prior art, the mobile device and its neighboring base stations are utilized to generate a plurality of line-of-sight (LOS) vectors to be taken into an artificial neural network, such as a back-propagation neural network (BPNN), to position the mobile device. Please refer to FIG. 1, which illustrates a schematic diagram of a conventional artificial neural network (ANN) 10. As shown in FIG. 1, the ANN 10 includes an input layer 100, a hidden layer 102 and an output layer 104. The input layer 100 receives the plurality of LOS vectors, the hidden layer 102 processes a calculation, and the output layer 104 outputs an estimated position of the mobile device corresponding to the calculation. The hidden layer 102 of the prior art can utilize a training model to adaptively receive the plurality of LOS vectors for continuous iteration calculation and to adaptively adjust a connective weighting value of the plurality of LOS vectors, so as to complete a training of the ANN 10 for correspondingly outputting the estimated position. However, during the iteration calculation of the prior art, it may result in complicated redundant calculation for the ANN 10 while the ANN 10 receives all the LOS vectors corresponding to the plurality of base stations. In the meanwhile, the complicated redundant calculation is accompanied by longer calculation periods, which is inconvenient for users' practical operation.